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https://issues.apache.org/jira/browse/PHOENIX-953?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14680981#comment-14680981
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James Taylor commented on PHOENIX-953:
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So when UNNEST is used in a SELECT, it's similar to a subquery and will produce
the cross product of the array elements? For example:
{code}
SELECT UNNEST(my_array) FROM t WHERE id = 1;
{code}
would produce one row per array element for the row with an id of 1?
Do you know of a good source of information on how UNNEST should work,
[~julianhyde]?
> Support UNNEST for ARRAY
> ------------------------
>
> Key: PHOENIX-953
> URL: https://issues.apache.org/jira/browse/PHOENIX-953
> Project: Phoenix
> Issue Type: Sub-task
> Reporter: James Taylor
> Assignee: Dumindu Buddhika
> Attachments: PHOENIX-953-v1.patch
>
>
> The UNNEST built-in function converts an array into a set of rows. This is
> more than a built-in function, so should be considered an advanced project.
> For an example, see the following Postgres documentation:
> http://www.postgresql.org/docs/8.4/static/functions-array.html
> http://www.anicehumble.com/2011/07/postgresql-unnest-function-do-many.html
> http://tech.valgog.com/2010/05/merging-and-manipulating-arrays-in.html
> So the UNNEST is a way of converting an array to a flattened "table" which
> can then be filtered on, ordered, grouped, etc.
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